I have the same problem. only way I can charge it is using a 12 watt power bank. When it is totally empty and I connect it to a wallcharger it will charge to 1% and if I do not touch it sometimes it charger to 100% (depending on the charger I use, 20w usb-c never past 1%, 15 watt usb-a charger sometime to 100 if the iPad is not disturbed.).
at least I can charge it sing the power bank and it is not totally bricked but my search for a wallcharger that works continues.
hope this can help.